The present invention is related to the textile industry and, more particularly, to the field of yarn handling and texturizing.
In the textile industry, handling and texturizing yarn for numerous applications can be quite important. Various systems have been developed for handling yarn which include virtual twisters such as shown in U.S. Pat. No. 5,775,079 titled xe2x80x9cApparatus For Imparting Virtual Twist To Strand Material And Method Of Imparting Samexe2x80x9d by Hoover, one of the co-inventors of the present application and also having the common assignee as the present application. Yarn stuffer boxes and yarn coilers have also been developed to assist in the process of texturizing yarn by forming crimps or undulations in the yarn with the use of a conveyor belt passing the crimped or undulations in the yarn through a heat oven. An example of such a coiler can be seen in U.S. Pat. No. 5,483,730 titled xe2x80x9cApparatus And Method For Forming Coils Of Yarn And For Heat Setting Samexe2x80x9d also by Hoover and also having the common assignee as the present application.
Nevertheless, there is still a need for systems and devices which further enhance the handling and texturizing of yarn.
With the foregoing in mind, the present invention advantageously provides an apparatus and methods for handling and texturizing yarn or other strand material which has an enhanced false twister that allows more even feed of the yarn through the twister and to a take-up source. The present invention also advantageously provides an apparatus and methods for handling and texturizing yarn or other strand material which effectively detects the presence or absence of yarn in a simple and less complicated way. The present invention additionally advantageously provides an apparatus and methods for handling and texturizing yarn which has a yarn take-up distance extender which provides the capability to greatly extend the distance between yarn being delivered to a source such as from a conveyor to the take-up source so that tangling and other problems with a plurality of strands being delivered at substantially the same time are reduced. The present invention further advantageously provides a yarn handling roller for more effectively separating and handling a plurality of strands thereacross at substantially the same time.
More particularly, the present invention provides an apparatus for handling and texturing yarn which preferably includes a yarn supply positioned to supply a plurality of strands of yarn, a false twister positioned downstream from the yarn supply for imparting a false twist to the plurality of strands of yarn, a yarn undulation former positioned downstream from the false twister for forming undulations in each of the plurality of strands of yarn, and a conveyor positioned to receive the plurality of yarn strands having undulations formed therein and for conveying the undulated strands of yarn downstream. The apparatus also preferably includes a heat setting oven positioned downstream from the yarn undulation former and to receive the conveyed yarn when passing therethrough to impart heat to the plurality of strands of yarn having undulations therein, a yarn sensor system positioned downstream from the heat setting oven for sensing the presence and absence of yarn being conveyed on the conveyor, a yarn take-up distance extender positioned downstream from the yarn sensor system for extending the distance of travel of the plurality of strands of yarn prior to take-up, and a yarn take-up source positioned downstream from the yarn take-up distance extender for receiving and taking up the plurality of strands of yarn.
The present invention also provides a yarn false twister for imparting a false twist to a plurality of yarn strands. The yarn false twister preferably includes bi-directional radial twisting means for twisting a plurality of yarn strands in two different radial directions to impart a false twist thereto and twist point distance extending means connected to the bi-directional radial twisting means for extending the twist point distance of the plurality of yarn strands.
The present invention additionally provides an electro-mechanical sensor system for sensing the presence and absence of yarn. The electro-mechanical sensing system preferably includes at least one electro-mechanical yarn detector including a yarn contacting portion thereof positioned to abuttingly contacting yarn being transported on a conveyor when being conveyed thereon and a switch which activates when the yarn contacting portion is in a first yarn contacting position when contacting strands of yarn and when the yarn contacting portion is in a second yarn contacting position when not contacting strands of yarn. The system also includes a controller connected to the switch for controlling the speed of the take-up of the yarn responsive to the activation of the switch so that yarn take up speed increases when yarn is present and yarn take up speed decreases when yarn is absent. The electro-mechanical yarn sensing system of the present invention can also include another electro-mechanical detector having a yarn contacting portion overlying the conveyor and abuttingly contacting yarn when passing thereon and connected to the conveyor and the controller so that the controller also controls the speed of the yarn being fed to the undulation former, e.g., controlling the speed of draw rolls.
The present invention still additionally provides a strand handling roller for handling a plurality of strands of material traveling over and abuttingly contacting therewith. The strand handling roller preferably includes a roller body having outer end portions having a larger circumference than inner medial portions thereof so that strands traveling over the roller body slidingly moves toward the inner medial portions when traveling over and abuttingly contacting the strand handling roller. The circumference of the roller body gradually decreasing from the outer end portions to the inner medial portions. The strand handling roller can also advantageously include the roller body further having a plurality of spaced-apart strand grooves formed in the inner medial portions thereof for assisting in separating and guiding the plurality of strands when traveling over and abuttingly contacting the strand handling roller.
The present invention further provides a yarn take-up distance extender for extending the distance from a conveyor to a yarn take-up source. The yarn take-up distance extender preferably includes a retractable distance extending member overlying a conveyor and which retracts to a first yarn threading position adjacent the end portion of the conveyor and extends to a second yarn take-up operating position an extended distance from the first yarn threading position and in a direction away from a yarn take-up source for increasing the distance that the plurality of yarn strands travel from the conveyor prior to being taken up by the yarn take-up source. The yarn take-up distance extender can also have the conveyor extending in a substantially horizontal plane substantially parallel to a horizontally extending floor, and the yarn take-up distance extender further including a distance extending boom member connected to and extending outwardly from the conveyor in a direction vertically transverse to the conveyor. The retractable distance extending member is preferably connected to the distance extending boom member.
The present invention still further provides a method of imparting a false twist to a plurality of yarn strands. The method preferably includes twisting a plurality of yarn strands in two different radial directions to impart a false twist thereto and extending the twist point distance of the plurality of yarn strands.
The present invention also still further provides a method of sensing the presence and absence of yarn traveling on a conveyor. The method preferably includes providing a yarn contacting portion thereof positioned to abuttingly contacting yarn being transported on a conveyor when being conveyed thereon, activating a switch when the yarn contacting portion is in a first yarn contacting position when contacting strands of yarn, activating the switch when the yarn contacting portion is in a second yarn contacting position when not contacting strands of yarn, and controlling the speed of the take-up of the yarn responsive to the activation of the switch so that yarn take up speed increases when yarn is present and yarn take up speed decreases when yarn is absent. The method can also include further controlling the speed of yarn being fed, e.g., by draw rolls, responsive to the activation of the switch.
The present invention yet further provides a method of handling a plurality of strands of material traveling over a roller. The method preferably includes slidingly moving a plurality of strands of material toward inner medial portions of a roller when traveling over and abuttingly contacting the roller. The slidingly moving step preferably includes traveling along an outer end portion of a roller body having a first circumference inwardly toward the inner medial portions having a second circumference. Also, the first circumference is preferably substantially larger than the second circumference. The method can also include using the roller to assist in separating and guiding the plurality of strands when traveling over and abuttingly contacting the strand handling roller.
The present invention yet still further provides a method of extending the distance from a conveyor to a yarn take-up source. The method preferably includes retracting a distance extending member to a first yarn threading position and extending the distance extending member to a second yarn take-up operating position an extended distance from the first yarn threading position and in a direction away from a yarn take-up source for increasing the distance that the plurality of yarn strands travel prior to being taken up by the yarn take-up source. The method can also advantageously include providing a conveyor which extends in a substantially horizontal plane substantially parallel to a horizontally extending floor and providing a distance extending boom member connected to and extending outwardly from the conveyor in a direction vertically transverse to the conveyor. The distance extending member is preferably connected to the distance extending boom member.